Keyword searches
The best way to perform a keyword search is by using a level filter of 1 and selecting the option Last level limit, with a limit of 1 page per domain.
Using keyword searches, the search engine's result pages will have a level of 0. Each result is an external link and will therefore have a level of 1. By setting the level filter to 1 you are telling Email Grabber to go through the search engine's result pages and follow every result.
Setting the Last level limit to 1 page per domain will tell Email Grabber to only scan the specific search result that the search engine provided. It will prevent Email Grabber from wasting time scanning other possible (level 1) pages of the same web site that are linked from the page the search engine pointed to.
To summarize, these settings will make Email Grabber go through all the search engine's result pages and scan each search result but not follow any other links on that particular search result page.